1 comment:

My impression is that it's usually quoted as an average family size, which might be slightly different. Just for another perspective, the Census's 2009 Current Population Survey says something like 1.96 for Average Number of People Under 18 per Family Household With Own Children Under 18 (Table AVG3 at http://www.census.gov/population/www/socdemo/hh-fam/cps2009.html).